Portable electronic equipment of course exists in many different types. One common example is a mobile terminal, such as a mobile telephone for a mobile telecommunications system like GSM, UMTS, D-AMPS, CDMA2000, FOMA or TD-SCDMA. Other examples include personal digital assistants (PDAs), portable media players (e.g. DVD players), palmtop computers, digital cameras, game consoles, navigators, etc. A mobile terminal in the form of a mobile telephone will be used as a non-limiting example of a portable electronic apparatus in the following.
Different kinds, or categories, of mobile terminals are currently offered on the market. A first category can be referred to as the “normal cell phone” type, having a display and a physical (mechanical) keypad with twelve keys representing digits 0-9 as well as characters * and #. This kind of keypad is commonly known as an ITU-T or a PIN-type keypad. In addition to the twelve keys, a mobile terminal of this first category often also has additional input elements, such as soft keys for call handling, etc., and input elements for display navigation, such as a set of arrow keys, a combined four or five-way navigation key, a joystick or a scroll wheel.
A further development of the first category is sometimes referred to as the BlackBerry® type. This type has a more extended set of keys, such as a physical keyboard of full QWERTY type (with one key for each typical key of a typewriter keyboard) or compact QWERTY type (where, for instance, each key may represent two adjacent keys of a typewriter keyboard), as well as any of the input elements for display navigation referred to above.
A different, second category of mobile terminals has a touch-sensitive display which can be operated by way of a stylus or the finger of a user. This second category, which is often referred to as “smartphone” or “PDA (personal digital assistant)”, therefore does not need a physical (mechanical) keypad (although some models of this category still contain a physical keypad in addition to the touch-sensitive display).
Whereas mobile terminals of the second category certainly have their benefits, there are nevertheless some drawbacks associated with them, in terms of a large apparatus size, high electric power consumption, and a high price. For many user segments, the first category of mobile terminals is therefore still preferred, wherein improvements to such mobile terminals are still desired.
Because of market demands, mobile terminals of the first category are minimal in physical size. Whereas this is beneficial from other perspectives, there is a problem to consider when it comes to their display navigation capabilities. Navigating by means of small arrow keys or a tiny joystick on a miniaturized terminal housing may be challenging.
In EP-1 197 835, an improvement is suggested where a mobile terminal is provided with a keypad which is adapted both for conventional key-pressing user actuation of individual keys and for navigating user actuation within a keypad area that includes the keys. To this end, the keypad—which has a keymat with a conventional twelve-key, ITU-T key layout—is provided with capacitive sensing plates integrally disposed beneath the keymat. In this way, the keypad of EP-1 197 835 can be used both in a conventional manner to enter alphanumeric data by pressing individual keys of the keypad, and as a touch pad by sliding a finger over the surface of the keymat to control a focus position (e.g. the position of a cursor) on the display. In effect, the touch-sensitive keypad of EP-1 197 835 can be used in much the same way as a mouse pad on a conventional laptop computer to navigate a cursor on the display. Also, selecting actions are performed as with a mouse pad on a laptop computer, i.e. by double-tapping on the mobile terminal's touch-sensitive keypad.
A problem that can be identified with the solution according to EP-1 197 835 is that due to the typical small size of a mobile terminal, it may be difficult to position the cursor accurately at the desired focus position. This has to do both with the fact that the keypad and display are quite small compared to a laptop computer, and because the mobile terminal is typically held in a non-stationary (hand-held) position. It may thus be even harder to perform a selecting action accurately, since not only must the focus position be navigated to correctly, but it must also be maintained in its correct position between the two taps of the double-tapping.
Therefore, there is still a need for improvements to a portable electronic apparatus, such as a mobile terminal, like the one in EP-1 197 835, having a display and a keypad adapted both for conventional key-pressing user actuation of individual keys and for navigating user actuation as a touch-pad within a keypad area that includes the keys.